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arXiv · 1211.1673

The Minimum-Mass Extrasolar Nebula: In-Situ Formation of Close-In Super-Earths

E. Chiang·G. Laughlin
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Abstract

Close-in super-Earths, with radii R = 2-5 R_Earth and orbital periods P < 100 days, orbit more than half, and perhaps nearly all Sun-like stars in the universe. We use this omnipresent population to construct the minimum-mass extrasolar nebula (MMEN), the circumstellar disk of solar-composition solids and gas from which such planets formed, if they formed near their current locations and did not migrate. In a series of back-of-the-envelope calculations, we demonstrate how in-situ formation in the MMEN is fast, efficient, and can reproduce many of the observed properties of close-in super-Earths, including their gas-to-rock fractions. Testable predictions are discussed.

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E. Chiang, G. Laughlin. 2012-11-07. The Minimum-Mass Extrasolar Nebula: In-Situ Formation of Close-In Super-Earths. https://doi.org/10.1093/mnras/stt424

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